1. Not all of a large system will be well designed.

2. Strategic Design Partnered in Scandinavia with Eric Evans Making Models Work in Large Projects Eric Evans Domain Language, Inc.

3. Not all of a large system will be well designed.

4. Ground Up Rebuild

7. Year 1 Year 2 Year 3 Legacy Replaced Exciting New Features

8. Let’s Refactor

10. domain A sphere of knowledge, influence, or activity. Define Domain

11. domain A sphere of knowledge, influence, or activity. The subject area to which the user applies a program is the domain of the software. Define Domain

12. Why bother with models?

13. The critical complexity of most software projects is in understanding the domain itself. Critical Complexity Is

14. What is a model?

16. Chinese Map

17. Mercator Map

18. model A system of abstractions that describes selected aspects of a domain and can be used to solve problems related to that domain. Define Model

19. model A system of abstractions that describes selected aspects of a domain and can be used to solve problems related to that domain. Define Model

20. model A system of abstractions that describes selected aspects of a domain and can be used to solve problems related to that domain. Define Model

21. A Model Serves a Particular Use.

22. Not “as realistic as possible”

23. A Model Serves a Particular Use. Not “as realistic as possible” Useful relative to specific set of domain scenarios

24. ubiquitous languageA language structured around the domain model and used by all team members to connect all the activities of the team with the software. Define Ubiquitous Language

25. context The setting in which a word or statement appears that determines its meaning. Define Context

26. There are always multiple models.

32. Rowing 8

33. “Context Map”

35. cooperative upstream/downstream

37. uncooperative upstream/ downstream

40. Custom House Currency Exchange System early 2006

41. Custom House Context Map

44. Custom House “SPOT” Model of Currency Exchange Deal

45. Object Interpretation of Implicit “TBS” Model

46. Explicit Translation

47. Custom House Currency Exchange System late 2006

48. Map What Is

49. Push Translation to the Borders

50. Single, Unified Model within Any One Context

51. (Where careful design is going on.)

52. Single, Unified Model within Any One Context No duplication...

53. Single, Unified Model within Any One Context No duplication...within a context! Duplication between...

54. Single, Unified Model within Any One Context No duplication...within a context! Duplication between...AOK!

56. Ground Up Rebuild

57. Let’s Refactor

58. The Enterprise Model One Ring to rule them all, One Ring to find them, One Ring to bring them all, and in the darkness bind them

59. Not all of a large system will be well designed.

60. Distilling the Core Domain

61. Generic Subdomains

62. Distilling the Core Domain Generic Subdomains Supporting Subdomains

63. Distilling the Core Domain Generic Subdomains Supporting Subdomains Core Domain

64. Distilling the Core Domain –What makes your system worth writing?

65. Distilling the Core Domain –What makes your system worth writing? –Why not buy it off the shelf?

66. Distilling the Core Domain –What makes your system worth writing? –Why not buy it off the shelf? –Why not outsource it?

67. Distilling the Core Domain –What makes your system worth writing? –Why not buy it off the shelf? –Why not outsource it?

68. Effort Distribution

72. Ground Up Rebuild Year 1 Year 2 Year 3 Legacy Replaced Exciting New Features

73. Which Part is Core?

75. Responsibility Traps …Or, Why do irresponsible programmers become heroes?

76. Let’s Hack

78. Which Parts are Core?

80. Responsibility Traps Building a platform to make other (lesser) programmers more productive. Cleaning up other people’s mess.

81. What’s a responsible designer to do?!!

82. How could we just build the core part?

83. Build Platform Based on Model

85. Strategy Draw a Context Map. Work with business leadership to define Core Domain. Design a platform that supports work in the Core Domain. Work with management to give freedom to the Core Domain Platform Context. Develop and model in the Core Domain.

86. Strategy Keep an eye on your Context Map. Keep working with business leadership as Core Domain narrows and shifts. Guard your platform that supports work in the Core Domain. Keep working with management to maintain freedom of the Core Domain Platform Context. Keep developing and evolving the model in the Core Domain.

87. Strategic DDD Resources www.domaindrivendesign.org Domain-Driven Design by Eric Evans PART 4! www.domainlanguage.com